Apparatus for refrigeration of atmospheric air.



No. 679,907. Patented Aug. s, mol.`

o. P.-osTEnGnEN\.

APPARATUS FOR REFRIGERATION 0F ATMOSPHERIG AIR.

(Application led Oct. 20, 1900.)

(No Model.)

UNITED STATES PATENT OFFICE.

OSCAR P. OSTERGREN, CF NEW YORK, Y., ASSIGNOR TO THE CSTERGREN MANUFACTURING COMPANY, OF NEW JERSEY.

AAPPARATUS FOR R'EFRIGERATION OF ATMOSPHERIC AIR.

SPECIFICATION forming part of Letters Patent No. 679,907, dated August 6, 1901.

Application filed October 20, 1900. Serial No. 335681. (No model.)

To all whom it may concern: for being compressed enters the compressing- Y Be itknown that I, OSCAR P. OSTERGREN, a cylinder through suction-valves o, and the subject of the King of Sweden and Norway, compressed air escapes through eductionand a resident of Bedford Park, borough ofl valves p into a cooler q, Where the air is fur- 5 Bronx, city and State of New York, have inther cooled by water circulating therein vented certain newand useful Improvements around the pipes s, through which the air in Apparatus for Refrigeration of Atmospasses, the water being supplied and dispheric Air, of which the following is a specicharged through suitable pipes t u. The 'cation. l power of this engine a is to be in excess of 6o 1o My invention consists of improvements the power to be expended in compressing the in apparatus for refrigerating and possiair. From the cooler q the compressed air bly liquefying atmospheric air by means-0f enters through inlet-valve e the compressing compression, cooling, and expansion of the end w of a combined compressing and eX- air, as hereinafter described, reference being panding cylinder of considerable length and 15 made to the accompanying drawings, in containing a long plunger-piston a, which is whichconnected by its rod y and the connecting- Figure 1 is mainly a vertical section of aprod z with the crank-shaftg of the steam-enparatus adapted for carrying out my invengine. The compressing part w of said cylintion, but some parts are shown in elevation. der is of somewhat greater length than the 7`o zo Fig. 2 represents a part of said apparatus in length of the movement of the piston and fits side elevation. Fig. 3 represents another the piston closely to enable further comprespart of said apparatus in side elevation. sion of the air and will, if necessary, inV prac- In cooling air through expansion the effect tice have suitable packing to hold the air and will be improved by heating the air during will have suitable means of lubricating the 2 5 expansion in doing useful work, (just as the closely-fitting parts. This compressing part best eect in compressing air is obtained by w of Y the combined cylinder is surrounded cooling it during compressiong) but as this by awater-jacket having circulating-pipes 4 can be done only partially, due to the limitaand 5 for further cooling the air while being tion of the cylinder-surface, it is necessary compressed. The compressed air is ejected 801 3o for best results to expandin stages with inthrough eduction-valve 6 into another cooler termediate heating, and as refrigeration is `'7 of like character as cooler q and passes on the ultimate purpose an especial advantage through inlet-valve 8 into the compressing will result if such heat be taken out of the end 9 of another long combined compresscompressed air which in turn is being exing and expanding cylinder, containing a 35 panded, which is the essential feature of my long plunger-piston 10, which is connected invention and which in the present instance I by its rod 11 and connecting-rod 12 with a seek to accomplish by the following appacrank 13 of the 4crank-shaft g. These are ratus. of like character as the first combined coma represents asteam-engine, which may be pressing and expanding engine, but of 9o 4o of any approved construction. b represents smaller diameter and adapted for edectan air-compressor,whereof the piston c is coning higher compression. The part 9 of said nected to the rodd of the engine-piston, and cylinder is also jacketed at 14 for the circupiston C is connected by its rod e 'and conlating of cooling-water through pipes 15 and necting-rod f with a crank-shaft g, carrying 16. The compressed air is ejected through 45 a suitable balance-Wheel h and suitably eduction-valve 17 into another cooler 18 and geared with the slide-valve 7l of said engine therefrom into a jacket 19 of the expanding by a rod j and eccentric 7c for working said part of the second combined engine. From valve. The cylinder of the air-compressor this jacket the compressed air is periodically has a jacket Z for circulating water for cooladmitted into the expanding part 19 of said 10o 5o ing the air while being compressed, with an cylinder under piston 10, through the inletinlet-pipe m and outlet n for the water. Air valve 20, to expand thereunder for being fur- 4arecut olf from like ports 23 of the cylinder` port face, according as the valve is turned one way or the other, said valve having an axial stem 24, on which is a crank 25, t which a rod'2l is attached, whiclrcarries roller-tappets 26, betweenwhich a cam 27 works to opcrate the valve, said-cam being carried on a shaft 28, which is geared with another shaft 29, that is geared with the crank-shaft g. The

bar 21 has a slot 30, by which it rides on shaft 28 for its support. 27 is calculated to open. and close the valve atthe proper limes for admission and cut-o,

as predetermined. A compression-spring 3l on the'stem` et' the valve between `the crank and the stuffing-box holds the valve on the valve-seat against the tendency of the compressed air to lift the valve. The exhaustvalveis another disk 32, having an axial stem 33'for operating it. The valve also has a compression-spring 34 on its stem to hold it on its seat. The ports are the same in this valve and its seat as in the other and like mechanism is employed for working it, as the crank35, rod 36, roller-tappets 37 on said rod, and cam 37a on shaft 28, said rod being slotted same as rod 2l for itssupport on shaft 28. The compressed air thus used and expanded in part 19 ofthe cylinder is by such expansion Acooled down below the air in the jacket and takes up heat therefrom duringexpansion for greater eiect on the piston. When .having thus expanded and accomplished its work in the cylinder, the expanded air is exhausted through pipe 38 into the counter-current apparatus 39 and ,throughv it into jacket 40 of part 4l of the first combined compressingaud expanding cylinder, from which it is .periodically admitted through valve. 42 into saidv partn4l of thecylinder under piston x for being further expanded and for applying part of its energy to the crank-shaft. vThe Valve 42 isof similar character as those employed in connection with expanding part 9 of t-he vsecond combined compressing and expanding engine and has a crank 43 on its stem 44, to which a rod-45 is connected, said rod having roller-tappets 46, actuated by a cam 47 on the shaft 28, said rod also being yoked onto said shaft by a slot same as the others, and a compressionspring 48 on the stem of valve holds it to its seat. Although heat is absorbed by the air during expansion in this cylinder from the Warmer air in jacket 40 to increasethe eiective energy under piston 0c, the temperature is Y nevertheless herein greatly reduced ,and possibly to the point of liquefaction of some of the air and when the piston @c is descending The contour ofthe cam the contents are exhausted throughvalve 49 Vthe lower part of jacket 40 into another pipe 52, connecting with. the receiver. The valve 49 is likewise a disk valve and' has a crank 53connected to its stem 54, and a rod 55 is connected to the crank and operated by a cam 56, working on rollertappets 57, said cam being carried on the shaft 29, on which the rod 55is yoked by a slot for its support. The air of the exhausting contents discharged into receiver 50 escapes through a coil 59 in jacket 40, thence through the counter-current device 39, and thence through another coil in jacket 19, wherefrom it may be discharged into the atmosphere, but is preferably economized by being discharged into the suction side of the compressor through a pipe 6l.

A The cold vapor is thus utilized in several stages of counter-current effects for gradual reduction of the air to be refrigerated. A relief-valve 62 in the pipe 6l, with means for graduating its action, regulates the pressure of the escaping vapor as desired.-

The expanding parts 19a and 4l of the combined compressing and expanding cylinders are made slightly largerthan the pistons for clearance-spaces in the localities where the low temperatures might when the apparatus is at rest stick the partstogether obstructively by freezing the moisture between them. In the compressing parts where the fit is close the heat generated by compression prevents such freezing.

Suitable drain-cocks, as 63, are connected with the counter-current device and the compressing and expanding cylinders for use when required.

Any greater number of the combined cornpressing and expanding engines than herein represented may be employed in the series Vas found best, and it is possible that the required refrigeration may be eected with one only of such engines, in combination with suitable power compressing and cooling apparatus ancillary thereto, and I do not limit myself to' a plurality of such-engines; but with a plurality arranged in series more economical results are obtained.

I am aware that it has been asserted that causing compressed air to expand while doing work in a cylinder with a piston,whereby the air was deprived of an amount of heat equivalent'to the work performed and then causing thek cold thus produced to be transferred to the compressed air passing to the expansion-engine, whereby it was assumed the temperature at the commencement vand termination of the expansion would continue to sink until liquefaction ensued, has not proved susceptible of practical application so far as regards the attainment of such low temperatures as are required for liquefying air, because it was not possible to maintainan IOO IIO

expansionengine in proper action at temperatures below the critical temperature of air=namely, 140 centigrade--nor to protect the engine-cylinder in which the expansion of air was eected sufficiently against the absorption of heatfrom the outside to enable such low temperature to be attained. I have anticipated these contingencies as probable in an expansion-engine of the nature to be understood from the foregoing dictum-viz', an engine doing work independently and in which it was sought to eect such expansionand I have therefore not only provided that the expansionengine shall only be auxiliary to a prime mover which shall maintain action of the expansion-engine and continue the expansion of the air to a greater extent than when the continuance of the expansion is dependent on the energy of the air being expanded, but have provided for the expansion in two or more stages in other auxiliary expansionengines, dividing the work so as to reach greater expansion in the iinal engine, even to the extent of not at all times contributing to the motive force, and thus affording greater efficiency of expansion and limitation of surface for absorption of heat from outside, the latter being due to the smaller capacity needed in the final expansion-cylinder, owing to the division of work. Since all known so-called permanent gases are kept up as gas on account of heat, and I have surely in my case a degenerating process that would work out all available heat in the atmospheric air, that is here at issue, we know that the molecules will come nearer together just in proportion as we reduce the heat in the gas. Nothing will stop the reduction of heat but the occurrence of liquefaction.

What I claim as my invention is l. In apparatus for refrigerating compressed air, the combination of air compressing and cooling apparatus, saidcompressing apparatus having power in excess of the power to be expended in compressing the air, a plurality of engines for utilizing the power of the compressed air and for expanding and cooling it, said engines arranged in series and being coupled with the compressing-engine, and means for regenerating the expanding air by heat absorbed from the compressed air prior to admission into the expanding=en gines, the said expandingengines together with the prime motor adapted to continue the operations of and the expansion in the terminal engine of the series however the expansive energy of the air therein maybe reduceda 2. In apparatus for refrigerating compressed air, a combined air compressing, and expanding, power-utilizing and air-cooling engine, as auxiliary to the prime-motor engine, consisting of a two-part cylinder of continuous structure, and a like plunger-piston working in both parts, the compressing par-ts of the cylinder and piston being close fitting and having a jacket and means for the circulation of a cooling iiuid around the parts subject to the heat of compression, and the expanding parts of the same being fitted with a clearance-space between the cylinder and plunger, and also having an air-regenerating jacket, and means whereby the compressed air enters the expanding part of the cylinder through said jacket,- said compressing and expanding parts of the cylinder having suitable inlet and outlet ports and valves, and said engine adapted with the aid of the primemotor engine to continue the'expansion of the air however its expansive energy may be reduced.

Signed at New York city this 15th day of October, 1900.'

OSCAR P. OSTERGREN. Witnesses:

C. SEDGWICK, J. M. HOWARD. 

